Volcanic Wines or a Glance at Volcanoes, Wine and Rocks

02Jul

Volcanoes have been getting a bad Press over the past few weeks, as
endless plumes of Icelandic ash have thrown Ireland and Europe into
air transport chaos.

Well, its time for some balance, time to tell the other side of the
Volcanic story, and in our story as you might guess, volcanoes are
heroic figures determined to create some of the finest vineyards and
wines the earth has ever known.

Most wine lovers are well aware that geology plays a huge part in
creating good wines, different types of soils and rocks produce huge
impacts on the grapes and the flavours of

A plate of Kimmeridge deposit, basically a chalky stone based clay,
forms a huge circular basin that very roughly would have Paris at its
centre and that runs north through Kent in England and south to Orlean
in France.

This was a giant sea basin millions of years ago, it was quite warm,
maybe even tropical and over millions of years, billions of shells
from dead crustaceans and indeed oysters fell to the bottom of this
large basin, they eventually became compacted into the white stone we
ordinarily call chalk like Kimmeridge.

The white cliffs of Dover are an exposed slice of this basin cut by
the English channel, but the same stone is under Champagne, Chablis,
Sancerre and Pouilly Fume. It is not surprising then that there is a
similarity to the wines of each of these areas, but the variation is
significant and also due to the stone.

The way in which the stone and soils affect a wines taste or the
success of a vineyard is not a simple as the taste of the rock gets
into the grape, though sometimes there are seemingly direct
connections. Sancerre is dominated by limestone Kimmeridge soils, the
wines are lean, acidic, green gooseberry and grassy. Lime and acid
seem to ooze from the very soil into the grapes. Just directly across
the river from the hilltop village of Sancerre is Pouilly Fume, with
its smokey notes of flint, the child’s toy cap gun smell in addition
to lime notes.

Pouilly Fume is part of the Kimerridge basin, but its soils contain
lumps of black crystals, and outcrops of larger blocks, these are
flint-stones, they are silica based crystals that form in gaps in
limestone amongst other places, but even with my poor geologic eye it
is clear that much of this rock could have been washed up from the
Loire over millions of years in the bend in the river that is Pouilly
Fume.

Somehow, the flint taste or an essence of it appears in the wines of
Pouilly Fume. The same grape planted the width of a river apart
produce to radically different tasting wines from the same Sauvignon
Blanc grape. The only major difference, because they get the same
weather, they face south and are often grown by the same families, is
the soil and rock underlying the vineyards.

Rock To Wine

The best scientific views on the link between geology and taste seem
to suggest that two big mechanisms are at play. Firstly the impact of
the rock itself, secondly the impact of weathering on the rocks and
how that alters the PH levels, mineral and metal content of the
vineyard soils.

This sounds complicated but can be explained very quickly, vines do
best in bad growing areas, they hate standing water and competition
from other plants.

Limestone, Granite and Basalt, a principle rock formed from volcanic
action, are rock forms that can create exactly the kinds of hostile
environments that are harsh for all other forms of agriculture, except
for vines.

So, the soils we want for great wine should be a death knell for any
sort of other agriculture.

Firstly just by being themselves, Limestone, Granite and Basalt can
help. Granite for example is immensely strong so during glaciations or
scouring by rivers, lumps of granite can be left behind as sheer
valley walls good for nothing except vineyards.

The Hill of Tain Hermitage is perhaps the most famous outcrop of
granite and hosts a dozen of the world’s most important vineyards
including Domaine Jaboulet’s La Chapelle Syrah vineyards which make
the Hermitage La Chapelle.

The impact of millions of years of weathering will however even affect
granite and then the second impact comes into play, hard rocks like
granite break down into shale or schist like soils. These drain and
dry out very quickly. However they also store heat and bring that heat
far into the soil. This acts as a lid for water which is retained at
great depth. This is hopeless for wheat and most agriculture, ideal
for a hot climate vineyard.

Softer stone like Limestone produces a soil and bedrock that is very
well drained, but with pockets of clay which acts like a sponge. It
also has the double whammy of being quite alkali, which most plants
hate and which can, burn, or in eco terms, help the break down of
organic materials in the soils. This often releases nutrients and
minerals which the vines with their huge roots can absorb.

It is these minerals, nutrients and metals that actually seem to be
responsible for the underlying tastes, perfumes and acidity levels in
the final wine.

Volcanic Action

While Sedimentary rock like limestone is essentially slow creation of
millennia, metamorphic and igneous rock like Basalt is the
instantaneous creation of volcanic action. It is what geologists call
extrusion material, lava and ash to you, I and Michael O’Leary.

This is hot, liquid material that cools into distinctive and sometimes
beautiful shapes as in Giants Causeway. It is mineral rich and as we
now all know too well volcanic ash contains silica, glass, sulphur and
in the right conditions sulphuric acid, but it contains far more than
that, volcanoes are home to latter day primordial ooze.

For thousands of years humans have been drawn to volcanic zones, many
civilisations have grown up at the foot of volcanoes and the ability
of volcanic regions to work miracles has long been understood.

Of course in addition to volcanoes themselves, the shallow pools of
hot water and mineral springs that their thermal outer zones create
has also been a draw since the dawn of civilisation.

Greek and Roman civilisation spent a great deal of time seeking out
such geothermal activity as did their wine makers. The Greek Island of
Santorini, the entire island of Sicily and every hot spring from
Athens to Bath drew Roman and Greek eyes, and tastebuds.

Volcanic Wine

The Greek island of Santorini is probably the home to the most famous
Volcanic wines in the world. The entire island population was
destroyed by a giant volcanic eruption around 1700 years BC. This
eruption covered the entire island in ash and lava. The basalt and
volcanic soils called aspa cover the entire island like chocolate
icing on a cake. There is almost no soil in an Irish sense of rich
organic mass. Volcanic rock tends frequently tends to look like
sponge, pock marked and occasionally hollow. These holes and voids
trap minerals in the unique, inorganic soil.

Best of all, what little water does fall is trapped in the rock
itself. This allows vines to burrow down and find the water even
though the ground looks like solid empty dry rock. Another unique
feature are fogs, which roll over the island, where the still warm
rock causes condensation, which trickles in through the porous
volcanic rock as if there has been rain.

Thanks to this unique volcanic landscape vines grow perfectly despite
a hopeless looking landscape. One additional factor is that being a
smooth lava formed island it is susceptible to wind, the winds are so
fierce indeed that they have created a unique method of planting. The
vines are woven into little baskets about a foot high and the grape
bunches are trained to grow inside the basket.

The wines of Santorini were as a result of all this thought to be a
gift from the gods with magical powers and highly sought after. The
most famous wine is the sweet wine of vinsanto.

Californian Hot Tub Wines

The hot tub culture in California is not a product of the sixties
Flower Power generation, nor the decadent 1970s. It is a direct result
of the impact of volcanic action, as it has been in Scandinavia and
ancient Rome.

Thermal pools and geysers top and tail California, one of the world’s
geologic hotspots. Napa Valley owes its physical structure and vinous
origins to volcanic action.

The Gold Rush that brought hundreds of thousands to flood westward
prompted the creation and expansion of wine production across the Napa
Valley to supply boomtowns like San Francisco and smaller settlements
all across Northern California.

More directly towns in the heart of Napa’s vineyards like Yountville
and Calistoga became boomtown themselves as they also marked the
starting point for prospectors being the starting gates of the
Silverado Trail leading from Napa Valley and its Volcano Mount Veeder
to the top of the geographic valley 200 miles north, America’s largest
active volcano Mount St. Helens.

Of course, the gold and silver that brought the boom was also a direct
result of volcanic action, lava soaks up minerals and metals like gold
and silver and concentrates them in seams, so the volcanic soils were
ideal for vines to supply wine to the gold miners that the lava had
also provided.

Clear signs of the excellence of volcanic and thermal soils for wine
can be seen in the Geyserville appellation, home to Stag’s Leap, the
red wine winner of the famous Paris Tasting in which US wines beat
France’s top chateaux. Nearby is Chateau Montelena, owned by Irishman
Jim Barret and the white wine winner of the Paris Tasting and star of
the film Bottleshock. On the edge of the Chateau Montelena vineyard, a
mineral rich volcanic soil that is producing some of the most dense
and complex Cabernet Sauvignon and home to the Californian Old
Faithful, a giant geyser that erupts every 30 minutes, everyday of the
year. Just don’t mention the words, eruption or lava.

A Beautiful Sicilian Menace

Europe’s most active volcano, despite the recent vocal protests from
Iceland, is Mount Etna. For all of recorded history it has been
actively erupting and spewing out lava, ash and complex minerals.

Despite the danger, almost every Mediterranean civilisation has
invaded or settled Sicily from the Phoenicians, to the Greeks,
Carthaginians, Romans and Francis Coppola.

They have built cities and planted vineyards. The suitable soils, and
underlying landscape, created by volcanism has proved ideal for vines.
The DO Etna, is perhaps the world’s only active volcano to have its
own Appellation Controllee. For now.

Nero D’Avola vines, are probably the most interesting on Sicily at
present and and produce dense, spicy and complex wines that used to
produce quite rustic wines, but over the last 5 years have been
arriving on Irish shelves as worthy and cheaper alternatives to
Australian Shiraz.